摘要
【目的】通过对河南省2001—2015年间不同时期(2001—2005、2006—2010及2011—2015年)冬小麦种植频率(winter wheat planting frequency,WWPF)时空变化及其主要影响因素定量分析,进一步明晰区域作物种植频率变化时空变化分布特征和主要影响因素顺序。【方法】以河南省为研究区,冬小麦为研究作物,在利用中低分辨率MODIS EVI时序遥感数据和CART决策树算法进行连续15年(2001—2015年)作物种植空间分布信息提取基础上,获取了研究区不同时期冬小麦种植频率空间信息。在此基础上,开展不同时期冬小麦种植频率时空变化分析,并利用相关分析、主成分分析和线性回归分析等数理统计方法对不同时期研究区种植频率变化的影响因素进行分析,最终确定主要影响因素的重要性排序。【结果】基于MODIS EVI时序遥感数据和CART决策树算法可获得河南省较高精度连续多年冬小麦种植空间分布信息,经验证,研究区冬小麦遥感提取平均总体精度为90.39%,Kappa系数在0.82—0.92之间,可满足区域冬小麦种植频率变化研究所需作物空间分布精度要求;通过分析河南省不同时期冬小麦种植频率时空变化信息,省域内冬小麦主产区大部分具有较高的冬小麦种植频率(WWPF>80%),而豫西南和豫南等山区由于地形复杂、自然条件较差导致冬小麦种植频率普遍较低(WWPF≤40%)。此外,3个时段期间,河南省冬小麦主产区高频种植冬小麦面积呈逐步增加趋势,WWPF>80%的面积比例分别为42.68%、59.94%和63.07%,低频种植面积呈减小趋势,WWPF≤40%的面积比例分别为28.53%、17.99%和16.63%,这对我国冬小麦主产区稳定粮食种植面积具有重要意义;从冬小麦种植频率影响因素分析结果看,河南省冬小麦种植频率与有效灌溉面积比例、土壤质量综合指数、播期气候适宜度、坡度和高程等指标间均存在显著的相关性,且除与坡度、高程呈负相关外,与其余因素均为正相关关系。以上指标对河南省冬小麦种植频率变化影响程度的排序结果为土壤综合质量指数>播期气候适宜度>有效灌溉面积比例>坡度(高程),即土壤质量>播期气候条件>灌溉条件>地形条件。【结论】通过对河南省冬小麦种植频率时空变化及其影响因素进行定量分析,明确了河南省冬小麦种植频率时空分布特征和变化规律,明晰了河南省区域冬小麦种植频率变化影响因素及其重要性排序,为开展作物种植面积变化分析提供了一定技术方法和思路借鉴,为区域农业土地利用决策模型构建提供一定基础理论支撑。
【Objective】Quantitative analysis was made on spatio-temporal variations of winter wheat planting frequency(WWPF)and its main influencing factors in different stages(2001-2005,2006-2010 and 2011-2015)in Henan province,in order to further clarify the characteristics of crop planting frequency change and the sequence of main influencing factors.【Method】In this study,winter wheat in Henan province was taken as the research crop.The spatial information of winter wheat planting frequency in different periods in the study area were obtained by extracting the spatial crop distribution information for 15 consecutive years(2001-2015)using mid-low resolution MODIS EVI time series remote sensing data and CART decision tree algorithm.On this basis,the spatio-temporal variations of winter wheat planting frequency in different stages were analyzed,and the influencing factors of the winter wheat planting frequency variations in different stages were investigated by correlation analysis,principal component analysis and linear regression analysis.Finally,the sequence of the main influence factors was determined.【Result】It was verified that the average overall precision of winter wheat extraction was 90.39%,and the Kappa coefficient was between 0.82 and 0.92,which could meet the requirements of spatial distribution accuracy of crops required for regional winter wheat planting frequency change research.By analyzing the spatial and temporal variation information of the winter wheat planting frequency in different periods in Henan province,most of the main winter wheat producing regions in Henan province had higher winter wheat planting frequency(WWPF>80%),while the planting frequency of winter wheat was generally lower in southwestern Henan and in mountainous areas of southern Henan due to complex topography and poor natural conditions(WWPF≤40%).In addition,during the three periods,the area of winter wheat planted at high frequency increased gradually in the main winter wheat producing areas of Henan province,the area proportion of WWPF>80% was 42.68%,59.94% and 63.07%,respectively.And the area planted at low frequency showed a decreasing trend,the area proportion of WWPF≤40% was 28.53%,17.99% and 16.63%,respectively,which were of great significance to stabilize the planted area of grain in the main winter wheat producing areas of China.According to the analysis results of influencing factors of winter wheat planting frequency,there was a significant correlation between the WWPF in Henan province and the ratio of effective irrigation area,soil quality comprehensive index,climate suitability at sowing stage,slope and elevation,etc.Besides the negative correlation between slope/elevation and WWPF,other factors were all positively correlated with WWPF.The ranking results of the above indicators affecting on the WWPF were as follows:soil comprehensive quality index>climatic suitability at sowing stage>effective irrigated area ratio>slope(elevation),that was to say,the soil quality>sowing date climatic condition>irrigation condition>topographic condition.【Conclusion】Based on quantitative analysis of spatio-temporal variations of winter wheat planting frequency and its influencing factors in Henan province,the spatio-temporal distribution characteristics and variation law of winter wheat planting frequency in Henan province were clarified,and the influencing factors and importance ranking of winter wheat planting frequency in Henan province were gotten,which could provide some technical methods and ideas for the analysis of crop planting area change,and provide some basic theoretical support for the construction of regional agricultural land use decision-making model.
作者
李方杰
任建强
吴尚蓉
陈仲新
张宁丹
LI FangJie;REN JianQiang;WU ShangRong;CHEN ZhongXin;ZHANG NingDan(Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences/Key Laboratory of Agricultural Remote Sensing,Ministry of Agriculture and Rural Affairs,Beijing 100081)
出处
《中国农业科学》
CAS
CSCD
北大核心
2020年第9期1773-1794,共22页
Scientia Agricultura Sinica
基金
国家自然科学基金(41871353,41801286)
中央级公益性科研院所基本科研业务费专项(1610132018016,1610132019026)、农业农村部农情遥感监测项目。
关键词
河南省
冬小麦
作物面积提取
作物种植频率
时空变化
影响因素
Henan province
winter wheat
crop area extraction
crop planting frequency
spatio-temporal variations
influencing factors